Polygon-inscriber.



B. DWOFSKY.

POLYGON INSGRIBER.

APPLIOATIOH FILED DB0.17.1909.

979,44@ Patented new?, 1910.

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martin emailing@ BERNARD DWOFSKY, 0F NEW YORK, N. Y., ASSIGNOR GFONE-HALF TO SAMUEL C.

NENMAN, 0F NE-W YORK, N.

POLGON-INSCRIBEB.

orarie.

Application filed December 17, 1.903.

Specification or Letters Fatent.

VFaitient-ed Dec. 2"?, itit).

Serial No. 533,542.

To all whom 'it may concern.'

Be it known that I, BERNARD Dworsirr, a subject of the Czar of Russia,who resides in the borough of Manhattan, city of New York, county andState of E' ew ilork. and whose post-ofiice address is care of EdwardNewman, No. 160 Broadway, N ew York city, New York, have inventedcertain new and useful Impr vements in Polygon-Inscribers, of which thefollowing is a clear, full, and exact description.

This invention relates to an instrument for use by draftsmen,machinists, and the like, for the purpose of easily and quicklypermitting the inscription of a polygon upon the end of a cylinder,concentric thereto.

Broadly considered, the invention consists of a pair of angular jawsmovable relatively to each other, the right hand side of one j aw beingalways parallel with the right hand side of the other, and the left handside of one being always parallel with the left hand side of the other,the apex of each angular jaw always being on a line which bisects theangle of cach jaw, and the angle formed by each jaw being a factor of360 degrees. F or example, if a hexagon is to bc produced, the jaw is ofan angle of 120 degrees. By placing one of the two angular jaws againstthe periphery of the cylinder, and tangential to it, and permitting theother angular jaw to come within the circumferential line, a pencil maybe readily drawn along the second jaw to enable one to inscribe twosides of the given polygon, and by successively shifting the jaws aroundthe cylinder the other sides may be produced.

The scope of my invention will be set forth in the claims.

In the accompanying drawings, Figure l is a plan view of my improveddevice as applied to a cylinder. Fig. :2 is a section on line 2 2, Fig.l. Fig. 3 is an end view of Fig. l. Fig. t is a view similar to Fig. 1,but with the supplementary guiding jaw omitted. Fig. 5 is a view of thegaging jaw with the sliding jaw removed.

In carrying out this invention, a gaging jaw l is provided of materialthickness. In the present instance, for the formation of a heXagon, theangle of this `iaw is 120 degrees. Extending from the jaw is a base 2,on each side of which are Vertical guides 3. A hole 4 with an opening 5for a thumbbroaden the range of my device for unusu-A ally largecyliuder', I provide an additional movable inw ll, provided with slotsl2,

Vmovable as was the jaw iO, and clamped in its position b vthun'ib-screws l2 passing through the said slots l2, and slots 13 in thejaw l0, engaging the base and thus enabling one to clamp the device inposition.

In order to inscribe a heXagon with the instrument of this inventionwhere it is desired to inscribe the same on the end of a cylinder, thedevice is placed against the end of the cylinder, (see Figs. 2 and 4f)so that the gaging jaw 'l will be tangential to the ,sides of thecylinder. The movable jaw is then moved up by the thumb-screw until the4apex of that Jaw coincides with the circumference of the cylinder. Thentwo lines are drawn along the movable `iaw as chords of two arcs. rIheinstrument is then moved so that the apex of the movable aw will againregister with the circumference, and with the free end of one of thechords, and a line again drawn, and such method continued throughout thecircumference.

In inscribing a polygon such as shown in Fig. l, one proceeds as beforedescribed, and draws two lines A, and B forming an angle of l2()degrees; he then moves his instrument until one of the legs of the anglecoincides with the line I5 drawn. line then drawn from the other end ofthe jaw or angle will meet the line B at the proper point. It will benoticed that the lines bisecting the two angles coincide.

In carrying out this invent-ion. details of construction may be variedfrom those shown, and yet the essence of the invention be retained; someparts might be employed without others, and new features thereof mightbe combined with elements old in the art in diverse ways, although theherein described type is regarded as embodying substantial improvementsover such modifications.

As many changes could be made in the above construction, and manyapparently widely dierent embodiments of the invention could be madewithout departing from the scope thereof, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted in an illustrative and not in a limiting sense. Itis furthermore desired to be understood that the language used in thefollowing claims is intended to cover all the generic and speciiicfeatures of the scope of the invention which as a matter of languagemight be said to fall therebetween.

I claim as my invention:

l. The herein described instrument for inscribing polygons on the end ofa cylinder consist-ing of a gaging jaw, a sliding jaw, each aw havingtwo sides at a definite angle to each other, the left hand side of oneaw being parallel with the left hand side of the other jaw, the righthand side of one being parallel with the right hand side of the other,and means for guiding and sliding the same so that the apices olf theangles of the two aws will always be on a line bisecting the angle ofthe two jaws.

2. The herein described instrument for inscribing polygons on the end ofa cylinder consisting of a gaging jaw, a sliding jaw, each jaw havingtwo sides at a deiinite angle to each other, the left hand side of onejaw being parallel with the left hand side of the other jaw, the righthand side of one being parallel with the right hand side of the other,and means for guiding and sliding the same so that the apices of theangles. of the two jaws will always be on a line bisecting the angle ofthe two jaws, and mechanical means for holding such movable jaw in theadjustedV position.

3. The herein described instrument for inscribing polygons on the end ofa cylinder consisting of a gaging jaw, a sliding jaw, each jaw havingtwo sides at a denite angle to each other, the left hand side of one jawbeing parallel with the left hand side of the other jaw, the right handside of one being parallel with the right hand side of the other, andmeans for guiding and sliding the same so that the apices of the anglesof the two jaws will be always on a line bis secting the angle of thetwo jaws, and a scale being -provided on one jaw and a cooperatingpointer on the other jaw.

Signed at New York city, N. Y. this 9th day of December 1909.

BERNARD DWOFSKY.

Witnesses ED. D. NEWMAN, SAUL NEWMAN.

